EP1149851B1 - Aliphatic thermoplastic polyurethane and its use - Google Patents

Abstract

Thermoplastic polyurethanes derived from hexamethylenedi-isocyanate and a polyol mixture based on polytetramethylene glycol, 1,6-hexanediol and optionally other polyols and chain extenders. Thermoplastic polyurethanes (TPU) derived from: (A) 100-60 mol% hexamethylenedi-isocyanate (HDI) and 0-40 mol% other aliphatic di-isocyanates; (B) 30-100 wt% polytetramethylene glycol (B1) and 0-70 wt% other polyols or polyol mixtures (B2) with a number-average mol. wt. (Mn) of 600-5000; (C) 80-100 wt% 1,6-hexanediol (C1) and 0-20 wt% other chain extender(s) with an Mn of 60-500; with the optional addition of (D) catalysts; and (E) conventional additives, etc. In this system, the equivalent ratio of (A):(B) = (1.5:1.0)-(10.0:1.0) and the NCO index is 95-105; the amounts of components (B1) and (B2) are 40-100 wt% and 0-60 wt% respectively if (B1) has an Mn of 600-1600, or 30-70 wt% and 70-30 wt% respectively if (B1) has an Mn of 200-590; components (C1) and (C2) are not the same as (B1). An Independent claim is also included for moulded products obtained from TPU as described.

Description

The invention relates to aliphatic thermoplastic polyurethanes (TPU) of hexamethylene diisocyanate, polytetramethylene glycol and hexanediol with improved properties.

Aromatic thermoplastic polyurethanes (aromatic TPUs) are not light stable because of their construction from aromatic diisocyanates. In the case of color settings of molded articles, the effect of light causes a strong yellowing and even with black shaped articles, the color and gloss level changes.

_n von 2000 und 40 bis 20 Gewichtsteilen eines Polydiols auf Basis Adipinsäure, Hexandiol und Neopentylglykol mit einem Molekulargewicht $\overline{\text{M}}$

_n von 2000. 1,6-Hexamethylendiisocyanat in einem Äquivalenzverhältnis von 2,8:1,0 bis 4,2:1,0, bezogen auf das Polyolgemisch, und 1,4-Butandiol als Kettenverlängerungsmittel, wobei das Äquivalenzverhältnis des 1,4-Butandiols bezogen auf das Polydiol 1,3:1,0 bis 3,3:1,0 beträgt, werden bevorzugt eingesetzt.DE-C 42 03 307 describes a thermoplastic polyurethane molding composition which can be processed thermoplastically in the form of sintered powder for producing grained sintered films, the powder being produced exclusively from linear, aliphatic components. The polyol component is composed of 60 to 80 parts by weight of an aliphatic polycarbonate diol having a molecular weight $\overline{\text{M}}$

_n of 2000 and 40 to 20 parts by weight of a polydiol based on adipic acid, hexanediol and neopentyl glycol having a molecular weight $\overline{\text{M}}$

_n of 2000. 1,6-Hexamethylene diisocyanate in an equivalence ratio of 2.8: 1.0 to 4.2: 1.0, based on the polyol mixture, and 1,4-butanediol as a chain extender, the equivalence ratio of the 1.4 Butanediols based on the polydiol 1.3: 1.0 to 3.3: 1.0, are preferably used.

This molding composition has the disadvantage (especially for optically demanding applications) that it tends to form a white deposit after storage (at room temperature and especially in accelerated aging tests such as climate change test, Arizona test and in the heat (60-95 ° C.)). The deposit formation that occurs has the further disadvantage that it is not easy to wipe off with a cloth.

Although the use of 1,6-hexanediol as a chain extender reduces the described deposit formation, it occurs again when stored at room temperature. However, this deposit formation can be removed by wiping with a cloth.

The object of the present invention was therefore to provide light-stable thermoplastic polyurethanes for high optical requirements which, especially after storage at room temperature and after an accelerated aging test (eg after storage at 60 ° C.), give moldings which show only very little or no deposit formation ,

This problem could be solved with the thermoplastic polyurethanes according to the invention.

• A) 100 bis 60 Mol-%, bevorzugt 100 bis 70 Mol-%, besonders bevorzugt 100 bis 80 Mol-% Hexamethylendiisocyanat (HDI) und 0 bis 40 Mol-%, bevorzugt 0 bis 30 Mol-%, besonders bevorzugt 0 bis 20 Mol-% andere, von HDI verschiedene, aliphatische Diisocyanate,
• B) 40 bis 100 Gew.-% Polytetramethylenglycol mit einem zahlenmittleren Molekulargewicht von 600 bis 1600 g/Mol und 0 bis 60 Gew.-% eines von Polytetramethylenglycol verschiedenen Polyols oder Polyolgemisches mit einem zahlenmittleren Molekulargewicht von 600 bis 5000 g/Mol und
• C) 80 bis 100 Gew.-% 1,6-Hexandiol und 0 bis 20 Gew.-% von 1,6-Hexandiol verschiedenen Kettenverlängerers mit einem zahlenmittleren Molekulargewicht von 60 bis 500 g/Mol,
  unter Zugabe von
• D) gegebenenfalls Katalysatoren und
• E) gegebenenfalls weiteren üblichen Hilfsmitteln und Zusatzstoffen,

wobei das Äquivalenzverhältnis von Diisocyanat A) zu Polyol B) zwischen 1,5:1,0 und 10,0:1,0 beträgt und wobei die NCO-Kennzahl (gebildet aus dem mit 100 multiplizierten Quotienten der Äquivalentverhältnisse von Isocyanatgruppen und der Summe der Hydroxylgruppen aus Polyol und Kettenverlängerungsmittel) 95 bis 105 beträgt.The present invention relates to aliphatic, thermoplastic polyurethanes obtainable from

• A) 100 to 60 mol%, preferably 100 to 70 mol%, particularly preferably 100 to 80 mol% of hexamethylene diisocyanate (HDI) and 0 to 40 mol%, preferably 0 to 30 mol%, particularly preferably 0 to 20 Mol% of other aliphatic diisocyanates other than HDI,
• B) 40 to 100 wt .-% polytetramethylene glycol having a number average molecular weight of 600 to 1600 g / mol and 0 to 60 wt .-% of a polyol or polyol mixture other than polytetramethylene glycol having a number average molecular weight of 600 to 5000 g / mol and
• C) 80 to 100% by weight of 1,6-hexanediol and 0 to 20% by weight of 1,6-hexanediol different chain extender having a number average molecular weight of 60 to 500 g / mol,
  with the addition of
• D) optionally catalysts and
• E) optionally further customary auxiliaries and additives,

wherein the equivalence ratio of diisocyanate A) to polyol B) is between 1.5: 1.0 and 10.0: 1.0 and wherein the NCO index (formed from the multiplied by 100 quotient of the equivalent ratios of isocyanate groups and the sum of Hydroxyl groups of polyol and chain extender) is 95 to 105.

• A) 100 bis 60 Mol-%, bevorzugt 100 bis 70 Mol-%, besonders bevorzugt 100 bis 80 Mol-% Hexamethylendiisocyanat (HDI) und 0 bis 40 Mol-%, bevorzugt 0 bis 30 Mol-%, besonders bevorzugt 0 bis 20 Mol-% andere, von HDI verschiedene, aliphatische Diisocyanate,
• B) 70 bis 30 Gew.-% eines von Polytetramethylenglykol verschiedenen Polyols oder Polyolgemisches mit einem zahlenmittleren Molekulargewicht von 600 bis 5000 g/Mol und 30-70 Gew.% Polytetramethylenglykol mit einem zahlenmittleren Molekulargewicht von 200-590 g/mol und
• C) 80 bis 100 Gew.-% 1,6-Hexandiol und 0 bis 20 Gew.-% Kettenverlängerer mit einem zahlenmittleren Molekulargewicht von 60 bis 5 00 g/Mol, der verschieden von Polytetramethylenglykol mit einem zahlenmittleren Molekulargewicht von 200 bis 590 g/mol und verschieden von 1,6-Hexandiol ist,
  unter Zugabe von
• D) gegebenenfalls Katalysatoren und
• E) gegebenenfalls üblichen Hilfsmitteln und Zusatzstoffen,

   wobei das Äquivalenzverhältnis von Diisocyanat A) zu Polyol B) zwischen 1,5:1,0 und 10,0:1,0 beträgt und wobei die NCO-Kennzahl (gebildet aus dem mit 100 multiplizierten Quotienten der Äquivalentverhältnisse von Isocyanatgruppen und der Summe der Hydroxylgruppen aus Polyol und Kettenverlängerungsmittel) 95 bis 105 beträgt.The present invention furthermore relates to aliphatic thermoplastic polyurethanes obtainable from

• A) 100 to 60 mol%, preferably 100 to 70 mol%, particularly preferably 100 to 80 mol% of hexamethylene diisocyanate (HDI) and 0 to 40 mol%, preferably 0 to 30 mol%, particularly preferably 0 to 20 Mol% of other aliphatic diisocyanates other than HDI,
• B) 70 to 30 wt .-% of a different polytetramethylene glycol polyol or polyol mixture having a number average molecular weight of 600 to 5000 g / mol and 30-70 wt.% Polytetramethylenglykol having a number average molecular weight of 200-590 g / mol and
• C) 80 to 100% by weight of 1,6-hexanediol and 0 to 20% by weight of chain extenders having a number average molecular weight of 60 to 5,000 g / mol, which is different from polytetramethylene glycol having a number average molecular weight of 200 to 590 g / mol and unlike 1,6-hexanediol,
  with the addition of
• D) optionally catalysts and
• E) optionally conventional auxiliaries and additives,

wherein the equivalence ratio of diisocyanate A) to polyol B) is between 1.5: 1.0 and 10.0: 1.0 and wherein the NCO index (formed from the multiplied by 100 quotient of the equivalent ratios of isocyanate groups and the sum of Hydroxyl groups of polyol and chain extender) is 95 to 105.

The above sequence of components A to E says nothing about the method of preparation of the TPU according to the invention. The TPUs according to the invention can be prepared in various process variants, these variants being equivalent to one another.

The novel TPUs based on two different aliphatic diisocyanates "A1" (HDI) and "A2" (aliphatic diisocyanate other than HDI) can be prepared, for example, in a reaction process for TPU "A1-2". However, it is also possible to prepare in a known manner firstly the TPU "A1" based on the aliphatic diisocyanate "A1" and separately the TPU "A2" based on the aliphatic diisocyanate "A2", the other components B to E being identical. Then TPU "A1" and TPU "A2" are then mixed in a known manner in the desired ratio to the TPU "A1-2" (for example with extruders or kneaders).

The TPUs based on polyol mixtures according to the invention can likewise be prepared by using polyol mixtures (polyol B1 and polyol B2) (for example in mixing units) in a reaction process for the TPU "B1-2". On the other hand in a known manner, first the TPU "B1" based on polyol "B1" and separately the TPU "B2" based on polyol "B2" are produced, the remaining components A and C to E are identical. Thereafter, then TPU "B1" and "B2" in a known manner in the desired ratio to the TPU "B1-2" mixed (eg with extruders or kneaders).

Depending on the requirements of the molded part, which is produced from the TPU according to the invention, the hexamethylene diisocyanate (HDI) can be partially protected against one or more other aliphatic diisocyanates, in particular isophorone diisocyanate (IPDI), 1,4-cyclohexane diisocyanate, 1-methyl-2,4- cyclohexane diisocyanate, 1-methyl-2,6-cyclohexane diisocyanate and isomer mixtures thereof, 4,4'-, 2,4'- and 2,2'-dicyclohexylmethane diisocyanate and isomer mixtures thereof.

For applications with lower light stability requirements, e.g. dark colored molding compositions parts (0 to 20 wt.%) Of the aliphatic diisocyanate may even be replaced by aromatic diisocyanates. These are described in Justus Liebigs Annalen der Chemie 562, pp. 75-136. Examples are 2,4-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, 4,4'-, 2,2'- and 2,4'-diphenylmethane diisocyanate, mixtures of 2,4- and 4,4'- Diphenylmethane diisocyanate, urethane-modified, liquid 2,4- and / or 4,4'-diphenylmethane diisocyanates, 4,4'-diisocyanatodiphenylethane (1,2) and 1,5-naphthylene diisocyanate.

As component B2) linear hydroxyl-terminated polyols having an average molecular weight of 600 to 5000 g / mol, preferably from 700 to 4 200 g / mol are used. Due to production, these often contain small amounts of nonlinear compounds. Therefore, one often speaks of "substantially linear polyols".

Suitable polyester diols can be prepared, for example, from dicarboxylic acids having 2 to 12 carbon atoms, preferably 4 to 6 carbon atoms, and polyhydric alcohols. Examples of suitable dicarboxylic acids are: aliphatic dicarboxylic acids, such as succinic acid, glutaric acid, adipic acid, suberic acid, Azelaic acid and sebacic acid and aromatic dicarboxylic acids, such as phthalic acid, isophthalic acid and terephthalic acid. The dicarboxylic acids can be used individually or as mixtures, for example in the form of an amber, glutaric and adipic acid mixture. For the preparation of the polyester diols, it may be advantageous to use, instead of the dicarboxylic acids, the corresponding dicarboxylic acid derivatives, such as carbonic diesters having 1 to 4 carbon atoms in the alcohol radical, carboxylic acid anhydrides or carbonyl chlorides. Examples of polyhydric alcohols are glycols having 2 to 10, preferably 2 to 6 carbon atoms, such as ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 2,2- Dimethyl 1,3-propanediol, 1,3-propanediol and dipropylene glycol. Depending on the desired properties, the polyhydric alcohols may be used alone or optionally mixed with each other. Also suitable are esters of carbonic acid with the diols mentioned, in particular those having 4 to 6 carbon atoms, such as 1,4-butanediol or 1,6-hexanediol, condensation products of hydroxycarboxylic acids, for example hydroxycaproic acid and polymerization of lactones, for example optionally substituted caprolactones. Preferably used as polyester diols are ethanediol polyadipates, 1,4-butanediol polyadipates, ethanediol-1,4-butanediol polyadipates, 1,6-hexanediol neopentyl glycol polyadipates, 1,6-hexanediol-1,4-butanediol polyadipates and polycaprolactones. The polyester diols have average molecular weights of 600 to 5000, preferably 700 to 4,200 and can be used individually or in the form of mixtures with one another.

Suitable polyether diols can be prepared by reacting one or more alkylene oxides having 2 to 4 carbon atoms in the alkylene radical with a starter molecule containing two active hydrogen atoms bound. Examples of alkylene oxides which may be mentioned are: ethylene oxide, 1,2-propylene oxide, epichlorohydrin and 1,2-butylene oxide and 2,3-butylene oxide. Preferably, ethylene oxide, propylene oxide and mixtures of 1,2-propylene oxide and ethylene oxide are used. The alkylene oxides can be used individually, alternately in succession or as mixtures. Suitable starter molecules are, for example: water, amino alcohols, such as N-alkyl-diethanolamines, for example N-methyldiethanolamine, and diols, such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol and 1,6-hexanediol. Optionally, mixtures of starter molecules can be used. Suitable polyether diols are also the hydroxyl-containing polymerization of tetrahydrofuran. It is also possible to use trifunctional polyethers in proportions of from 0 to 30% by weight, based on the bifunctional polyethers, but at most in such an amount that a thermoplastically processable product is formed. The substantially linear polyether diols have molecular weights of from 600 to 5,000, preferably from 700 to 4,200. They can be used both individually and in the form of mixtures with one another.

As chain extender C) 1,6-hexanediol is used, optionally in admixture with up to 20 wt .-% of 1,6-hexanediol and polytetramethylene glycol having a number average molecular weight of 200 to 590 g / mol various chain extenders having a number average molecular weight of 60 to 500 g / mol, preferably aliphatic diols having 2 to 14 carbon atoms, such as Ethanediol, diethylene glycol, dipropylene glycol and especially 1,4-butanediol, or (cyclo) aliphatic diamines, e.g. Isophoronediamine, ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, N-methyl-propylene-1,3-diamine, N, N'-dimethylethylenediamine. In addition, smaller amounts of triols can be added.

For applications with lower light stability requirements, for example with dark-colored molding compositions, parts of the aliphatic diols and diamines (up to 20% by weight, based on chain extender) can be replaced by aromatic diols and diamines. Examples of suitable aromatic diols are diesters of terephthalic acid with glycols having 2 to 4 carbon atoms, such as terephthalic acid-bis-ethylene glycol or terephthalic acid-bis-1,4-butanediol, hydroxyalkylene ethers of hydroquinone, such as 1,4-di (-hydroxyethyl) hydroquinone , and ethoxylated bisphenols. Examples of suitable aromatic diamines are. 2,4-tolylene-diamine and 2,6-toluenediamine, 3,5-diethyl-2,4-toluenediamine and 3,5-diethyl-2,6-toluenediamine and primary mono-, di-, tri- or tetraalkyl-substituted 4,4'-diaminodiphenylmethanes.

Furthermore, it is also possible to use customary monofunctional compounds in small amounts, e.g. as chain terminators or demoulding aids. Examples include alcohols such as octanol and stearyl alcohol or amines such as butylamine and stearylamine.

The TPUs of the invention can be prepared by the known tape or extruder processes (GB-A 1,057,018 and DE-A 2,059,570). The method according to PCT / EP 98/07753 is preferred.

Preferably, a catalyst is used in the continuous production of the thermoplastic polyurethanes according to the extruder or belt process. Suitable catalysts are those known in the art and conventional tertiary amines, e.g. Triethylamine, dimethylcyclohexylamine, N-methylmorpholine, N, N'-dimethylpiperazine, 2- (dimethylaminoethoxy) ethanol, diazabicyclo [2,2,2] octane and the like, and especially organic metal compounds such as titanic acid esters, iron compounds, tin compounds, e.g. Tin diacetate, tin dioctoate, tin dilaurate or the Zinndialkylsalze aliphatic carboxylic acids such as dibutyltin diacetate, dibutyltin dilaurate or the like. Preferred catalysts are organic metal compounds, in particular titanic acid esters, iron or tin compounds. Very particular preference is given to dibutyltin dilaurate.

In addition to the TPU components and optionally catalysts, it is also possible to add UV stabilizers, auxiliaries and additives. Mention may be made, for example, of lubricants such as fatty acid esters, their metal soaps, fatty acid amides and silicone compounds, antiblocking agents, inhibitors, hydrolysis stabilizers, heat and discoloration, flame retardants, dyes, pigments, inorganic and organic fillers and reinforcing agents prepared by the prior art and also may be applied with a sizing. Details The specialist literature can be found on the abovementioned auxiliaries and additives, for example JH Saunders, KC Frisch: "High Polymers", Volume XVI, Polyurethanes, Parts 1 and 2, Interscience Publishers 1962 and 1964, R. Gächter, H. Müller ( Ed.): Paperback of the plastic additives, 3rd edition, Hanser Verlag, Munich 1989 or DE-A-29 01 774.

The addition of additives may take place after the polymerization by compounding or during the polymerization. During the polymerization, for example, antioxidants and UV stabilizers can be dissolved in the polyol. However, it is also possible to add lubricants and stabilizers in the extruder process, for example in the second part of the screw.

The TPUs according to the invention can be used for the production of moldings, in particular for the production of extrudates (for example films) and injection-molded parts. Furthermore, the TPUs according to the invention can be used as a sinterable powder for the production of fabrics and hollow bodies.

The invention will be explained in more detail with reference to the following examples.

Examples Production of TPU and splash plates

The TPUs were continuously prepared as follows:

Component B), which additionally contains auxiliaries (see Table), chain extender C) and dibutyltin dilaurate were heated in a kettle with stirring to about 110 ° C and together with the component A), which by means of heat exchangers to about 110 ° C. was thoroughly mixed by a static mixer from Sulzer (DN6 with 10 mixing elements and a shear rate of 500 s ^-1 ) and then fed into the feeder of a screw (ZSK 32). The entire mixture reacted on the extruder until complete reaction and was then granulated.

The granules produced were dried and then sprayed in each case to several spray plates. A part of the spray plates was stored in a circulating air dryer at 60 ° C and tested for surface buildup. Another part of the splash plates was stored at room temperature. The formation of deposits is particularly good to recognize fingerprints, which are located on the molding. The evaluation of the samples was qualitative, since a measuring method is not known.

test conditions

Rectangular splash plates (125 mm x 50 mm x 2 mm) were produced from the TPU.

_n = 2000 g/mol PE 225B Polybutandioladipat mit mittlerem Molekulargewicht $\overline{\text{M}}$

_n = 2250 g/mol Therathane 2000® Polytetrahydrofurandiol mit $\overline{\text{M}}$

_n = 2000 g/mol (Firma Du Pont) Therathane 1000® Polytetrahydrofurandiol mit $\overline{\text{M}}$

_n = 1000 g/mol (Firma Du Pont) Therathane 650® Polytetrahydrofurandiol mit $\overline{\text{M}}$

_n = 650 g/mol (Firma Du Pont) Therathane 250® Polytetrahydrofurandiol mit $\overline{\text{M}}$

_n = 250 g/mol (Firma Du Pont) Acclaim® 2220 Polyetherpolyol mit Polyoxypropylen-Polyoxethyleneinheiten (mit ca. 85% primären Hydroxylgruppen und einem mittleren Molekulargewicht von $\overline{\text{M}}$

_n von ca. 2000 g/mol Fa. Lyondell) HDI Hexamethylendiisocyanat Irganox® 1010 Tetrakis[methylen-(3,5-di-tert-butyl-4-hydroxyhydrocinnamate)]methan (Fa. Ciba Geigy) Stabaxol® P200 Aromatisches Polycarbodiimid (Fa. Rhein-Chemie) 1,4BDO 1,4-Butandiol 1,6 HDO 1,6-Hexandiol

Qualitative assessment (increasing deposit formation):
none <very low <slight <distinct <strong <very strong DBTL dibutyltindilaurate DE2020 1,6-hexanediol-based medium molecular weight polycarbonate diol $\overline{\text{M}}$

_n = 2000 g / mol PE 225B Medium molecular weight polybutanediol adipate $\overline{\text{M}}$

_n = 2250 g / mol Therathane 2000® Polytetrahydrofurandiol with $\overline{\text{M}}$

_n = 2000 g / mol (Du Pont company) Therathane 1000® Polytetrahydrofurandiol with $\overline{\text{M}}$

_n = 1000 g / mol (Du Pont company) Therathane 650® Polytetrahydrofurandiol with $\overline{\text{M}}$

_n = 650 g / mol (Du Pont company) Therathane 250® Polytetrahydrofurandiol with $\overline{\text{M}}$

_n = 250 g / mol (Du Pont company) Acclaim® 2220 Polyether polyol with polyoxypropylene-polyoxyethylene units (containing about 85% primary hydroxyl groups and an average molecular weight of $\overline{\text{M}}$

_n of about 2000 g / mol Fa. Lyondell) HDI hexamethylene diisocyanate Irganox® 1010 Tetrakis [methylene (3,5-di-tert-butyl-4-hydroxyhydrocinnamate)] methane (Ciba Geigy) Stabaxol® P200 Aromatic polycarbodiimide (Rhein-Chemie) 1,4BDO 1,4-butanediol 1.6 HDO 1,6-hexanediol

Results:

Claims (5)

1. Thermoplastic polyurethanes obtainable from

   A) 100 to 60 mol% of hexamethylene diisocyanate (HDI) and 0 to 40 mol% of other aliphatic diisocyanates,

   B) 30 to 100 wt.% of polytetramethylene glycol having a number average molecular weight of 600 to 1600 g/mol or of 200 to 590 g/mol (B1) and 0 to 70 wt.% of a polyol or polyol mixture (B2) differing from (B1) and having a number average molecular weight of 600 to 5000 g/mol and

   C) 80 to 100 wt.% of 1,6-hexanediol (C1) and 0 to 20 wt.% of a chain extender differing from (C1) and having a number average molecular weight of 60 to 500 g/mol (C2),
   with the addition of

   D) optionally catalysts and

   E) optionally conventional auxiliary substances and additives,

   wherein the equivalence ratio of diisocyanate A) to polyol B) is between 1.5:1.0 and 10.0:1.0 and wherein the NCO index is 95 to 105,
   and wherein, in the case of a number average molecular weight of (B1) of 600 to 1600 g/mol, (B1) is present in a quantity of 40 to 100 wt.% and (B2) is present in a quantity of 0 to 60 wt.% and, in the case of a number average molecular weight of (B1) of 200 to 590 g/mol, (B1) is present in a quantity of 30 to 70 wt.% and (B2) is present in quantity of 70 to 30 wt.%, wherein (C1) and (C2) differ from (B1).
2. Use of the thermoplastic polyurethanes according to claim 1 for the production of mouldings.
3. Use of the thermoplastic polyurethanes according to claim 1 for the production of extrudates and injection moulded articles.
4. Use of the thermoplastic polyurethanes according to claim 1 as a sinterable powder for the production of sheet products and hollow articles.
5. Mouldings obtainable from a thermoplastic polyurethane according to claim 1.